<![CDATA[Heart disease is one of the leading non-communicable diseases worldwide, with a continuously increasing prevalence and a high mortality rate. Potassium plays an important role in maintaining normal cardiac function. Imbalances in potassium levels may lead to serious complications in patients with heart disease. Although dietary potassium intake is considered an important determinant of potassium homeostasis, evidence regarding the relationship between potassium intake and serum potassium levels among hospitalized patients with heart disease remains limited and inconsistent. This study aimed to determine the association between potassium intake and serum potassium levels among patients with heart disease at Jombang Regency General Hospital. This quantitative study employed a cross-sectional design. The study population consisted of all patients with heart disease hospitalized at Jombang Regency General Hospital between March-June 2026 which represented the available patient population at the study site during the study timeframe. A total sampling technique was used, resulting in 44 respondents. Primary data on potassium intake during the previous month were collected through interviews using a Semi-Quantitative Food Frequency Questionnaire (SQ-FFQ). Secondary data on serum potassium levels were obtained from electronic medical records. Data were analyzed using descriptive statistics and the Spearman correlation test with a significance level of 0.05. Most respondents were in the late adulthood age group (46–65 years) (81.8%), male (61.4%), self-employed (36.4%), had a senior high school education (61.4%), had previously received nutrition education (61.4%), and had normal nutritional status (50.0%). The majority of respondents had normal potassium intake (68.2%) and normal serum potassium levels (65.9%). Spearman correlation analysis revealed a significant positive association between potassium intake and serum potassium levels (p < 0.001; r = 0.894). There was a significant association between potassium intake and serum potassium levels among patients with heart disease. However, the findings should be interpreted with caution, as serum potassium levels may also be influenced by clinical factors such as renal function, medication use, and fluid balance.]]>
